Process of fixing and impermeabilizing soil masses



Feb. 13, 1940. J. VAN HULST 2,190,003

PROCESS OF FIXING AND IMPERMEABILIZING SOIL MASSES Filed June 16, 1936r/Ver [zed INVENTOR L/A/V I A/v H0457 ELM ATTO R N EY Patented Feb. 13,1940 UNITED STATES PATENT OFFICE PROCESS OF FIXING AND IMIPERMEABILIZ-ING SOIL MASSES Application June 16, 1936, Serial No. 85,530 In theNetherlands July 19, 1935 3 Claims.

This invention relates to a process for fixing and immobilizing, andcontingently impermeabilizing sand and earth masses, particularly suchas are in permanent or intermittent contact with 6 water with a freewater level, as is the case, for

, instance, with river-beds, shores, beaches, sandbanks or shoals alongcoasts or in tidal rivers, canaland riversides, dikes, seawalls, moles,breakwaters, and the like.

- The process according to the present inven tion constitutes a furtherimprovement of the processes described in my prior U. S. applicationsSerial No. 668,033, filed April 26, 1933, Serial No. 25,184, filed June5, 1935 (Patent No. 2,158,025,

15 May 9, 1939) Serial No. 25,379, filed June 7, 1935 (Patent No.2,075,244, March 30, 1937) Serial No. 51,602, filed November 26, 1935(Patent No. 2,051,505, August 18, 1936); Serial No. 59,490, filedJanuary 17, 1936; and Serial No. 60,062, filed 20 January 21, 1936,according to which processes pervious or loose subsoil layers and othermasses are impermeabilized and/or fixed by causing aqueous dispersionsof bituminous substances, which may also contain finely-divided filling25 substances, to penetrate into the soil or mass under treatment and tocoagulate at the desired place or depth.

In applying said prior processes for fixing and immobilizing sand andearth masses, which are 80 in permanent or intermittent contact withwater with a free water level, difliculties may arise in consequence ofthe mass thus treated still having insufilcient cohesion to resist theerosive action of the running water or waves.

85 It is also known to fix shores, banks and the like by providing astone-setting or stone-dumping, but then there is the risk of thesand orearth behind or underneath the stones being washed away, with the resultthat the stone-setting or stone-dumping may fall into decay orsubsidence after some lapse of time. Such stone-dumpings are alsoapplied for protecting the bottom of rivers and canals, or in makingconstructions in the sea in order to prevent 46 erosion of the soil, buteven when, for instance,

a wattle-work is used as a basis for the dumping it may occur that theunderlying earth is washed away.

I have now found that sand or earth masses,

50 which are in permanent or intermittent contact with running water,sea waves or other water with a free water level, can be fixed andimmobilized, and contingently impermeabilized,

by the use of aqueous dispersions of bituminous 55 substances, asphalt,tar, pitch, parafiin wax,

resins, rubber or the like, or mixtures thereof, or mixtures of suchdispersions with finely divided filling substances, in the manner asdescribed in the above-mentioned prior patent applications incombination with the application on top thereof of some coarse material,such as a stone-setting or a stone-dumping, or a covering with mats,plaited screens, wattle-work, osiery, reed or the like, or such acovering with on top thereof a stone setting or dumping. Said coarse 0materials may be applied either before or after the treatment of thesand or earth mass with the dispersion. On the one hand the said coarsematerials protect the earth mass impregnated with bitumen or otherdispersed substances against the erosive action and wash of' the'runningwater and waves, while on the other hand the stone-setting,stone-dumping or other covering is protected against collapse orsubsidence, since the impregnated, underlying sand or earth can nolonger be washed away.

The aqueous dispersions to be used in the present process must beadapted to the soil to be treated, just as is the case when applying theprocesses described in the above-mentioned prior applications. Fillersto be added to the dispersions of bituminous or the like substances are,for example, colloidal clay, Portland cement, lime, limestone powder,fine sand, micro-asbestos, infusorial earth, trass, shale powder, coal 0dust and the like. The dispersed bitumen may also be treated withsubstances which tend to improve the adhesion of the bitumen to mineralaggregates, such as heavy metal soaps, high molecular organic acids andthe like. The bind- 5 ing capacity of the bitumen may also be improvedby adding to the dispersion a few percents of rubber latex or rubber.dispersion. I In the accompanying drawing, Figure I,II, and IIIillustrate the manner of carrying out the 40 invention according to theembodiments thereof described below in Examples I, II and III,respectively.

Example I This relates to the repairing of a shore protection consistingof a stone-setting on a sandy subsoil, said setting having wholly orpartly collapsed owing to the sand having been carried away by thewashof the waves.

After the stone-settinghas been replaced in its original position, pipesare inserted in the subsoil close behind and parallel with thestonesetting. These pipes, the bottom ends of which are open, are filledwith gravel up to a certain level. A bitumen dispersion containing 10%bitumen and 2% clay, prepared with soap as emulsifier and, if necessary,with the addition of a known stabilizing agent, is injected into thepipes. the pipes are slowly pulled up so as to allow the dispersion tospread regularly over the whole height of the shore wall and to producea proper impregnation of the sand layer underlying the stone-setting.The stability of the dispersion is regulated so as to produce itscoagulation after a suitable time of contact with the soil constituents,whereby the desired cohesion is obtained.

Example I I This relates to the local fixing of a sea floor with a viewto the construction of a mole, in order to prevent the washing away ofthe soil from underneath .the mole construction. A series of injectionpipes, which may be inter-connected, are introduced into the soil at adepth of about 50 cm., and through these pipes a 30% bitumen dispersionis injected, containing as emulsifier 1% wood tar and 0.5% sodiumhydroxide, both ingredients calculated on the weight of bitumen. Whilethe dispersion is injected the pipes may preferably be pulled in thehorizontal direction through the sea floor or shifted in some other way,the soil thus being more or less loosened, which promotes the injection.Thereafter the mole is constructed in a known manner by setting ordumping stone.

Example III This relates to the fixing of a sandy river-bed. A caissonorbell-shaped body is let down onto the bottom of the river, theside-walls of the said body being caused to sink partly into the soil.An aqueous dispersion containing 20% hard bitumen, prepared with 2%naphthenic acids and 0.5% sodium hydroxide (calculated on bitumen) asemulsifier, and to which 10% rubber latex (calculated on the totalweight of dispersion) has been added, is pumped into the hollow spaceDuring the injection of the dispersion of the caisson above the soil.The dispersion will penetrate into the soil, the quantity of dispersionbeing such that the soil is impregnated to a sufiicient depth, and itsstability being such as to secure coagulation after a short time. Afterthe caisson has been removed, the impregnated river-bed is covered withstones.

I claim: I

1. A process for fixing and impermeabilizing soil masses, particularlythose in contact with freely moving water, comprising applying animpregnating material including a dispersion of a binding agentcoagulable in situ to an upper layer of the soil mass and applying acovering of'a coarse, relatively heavy material over the surface of thesoil mass whereby to protect said impregnated layer against the erosiveaction of running water in contact therewith, and whereby said coveringis protected by said impregnated soil mass from collapse or subsidence.

2. A process for fixing and impermeabilizing soil masses, particularlythose in contact with freely moving water, comprising impregnating anupper layer of the soil mass with an aqueous dispersion of bitumencoagulable in situ, and applying over the soil mass thus impregnated acovering of a coarse, relatively heavy material whereby to protect saidimpregnated layer against the erosive action of running-water in contacttherewith, and whereby said covering is protected by said impregnatedsoil mass from collapse or subsidence. r

3. A process for fixing and impermeabilizing soil masses, particularlythose in contact with freely moving water, comprising covering thesurface of the soil mass with a coarse, relatively heavy material andimpregnating the upper portion of the soil mass beneath the coarse,rela-' tively heavy material with an aqueous dispersion of bitumencoagulable in situ whereby said material is protected against collapseor subsidence and said impregnated portion of the soil is protected bysaid material against the erosive action of running water.

' I JAN VAN HULST.

